An answer to your question all depends on what YOU consider major suttas. There are major suttas in each of the five Nikayas (the
Khuddaka Nikaya being a compendium of several volumes among which are included the
Dhammapada, the
Udana, the
Itivuttaka, and the
Sutta Nipata all of which I would recommend as having essential discourses in them).
But if you are looking for the best translations that are currently available for any or all of the discourses of Gotama, your best bet would be to invest in the four volume set of the four major Nikayas (the
Digha,
Majjhima,
Samyutta, and
Anguttara Nikayas) published by Wisdom Publications. You can find links to these in the following thread, together with even more recommendations for your reading and clarification pleasure:
Essential Books from Theravadin ResourcesNow, if all you're interested in are sutta about meditation, I would recommend purchasing the Majjhima Nikaya (translated by Bhikkhu Nanamoli and edited by Bhikkhu Bodhi) along with the Anthology of
The Numerical Discourses of the Buddha translated by Nyanaponika Thera and edited by Bhikkhu Bodhi. Why do I recommend these books in particular? Because of the wealth of the knowledge contained in the footnotes which help to clarify important sections of the text. I haven't had an opportunity yet to fully read Bodhi's newest translation (
The Numerical Discourses of the Buddha) so I'm unable to provide an opinion about that. However, if it is anywhere near the quality of any of the other volumes that Bodhi has had a hand in assisting to publication, I expect it will also be a treasure to have and to read.
I would not recommend Bhikkhu Bodhi's anthology of discourses published in his
In the Budddha's Words as I do not care for the translations in that volume. However, the volume is worth reading for the value of the Introductions that Bodhi has written to to each major section of suttas in that book. There are ten different sections and therefore ten Introductions which are very well written and researched as far as their relevance to explaining the Dhamma and the path to awakening.
As for understanding the Dhamma itself, I would recommend the two older volumes of discourses beginning with the
Samyutta Nikaya (and of course the
Anguttara Nikaya). Once again, the Introductions (as well as the footnotes) in the
Samyutta Nikaya are very well written and bring out several important points about the Dhamma. Both these volumes are, according to scholars, among the oldest texts available of the discourses. The
Sutta Nipata as well as other volumes from the
Khuddaka Nikaya are also considered older in origin. These older texts are quite extraordinary in their clarity and ability to convey the original texture and intent of the Dhamma. They are the closest we have available to actually listening to original explanations of the Dhamma from the source himself.
Have fun.